<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0">
        <meta http-equiv="X-UA-Compatible" content="ie=edge">
        <title>Document</title>
        <!--
        * @作者: 陈会丽 *
        * @时间：2024-2025-1 *
        -->
    </head>
    <body>
        <div></div>
        <style>
            body{
                background-color: bisque;
                
            }
            div{
                width: 200px;
                height: 200px;
                background:linear-gradient(white 50%,black 50%);
                margin:20px auto;
                display: flex;
                align-items: center;
                border-radius: 50%;
            }
            div::after{
                content: "";
                width: 100px;
                height: 100px;
                display: block;
                background:radial-gradient(black 25%,white 25%);
                border-radius: 50%;
            }
            div::before{
                content: "";
                width: 100px;
                height: 100px;
                display: block;
                background:radial-gradient(white 25%,black 25%);
                border-radius: 50%;
            }
        </style>
    </body>
</html>